We therefore compared 5 scoring systems in the assessment of the risk of 30-day mortality in 3214 patients with STEMI treated with primary percutaneous coronary intervention (PCI).
Clinical scores showed a large variability in risk stratifying patients. Identification of high-risk patients ranged from 15 % (PAMI score ?#xA0;9) to 66 % (McNamara definition). McNamara, Antoniucci and Brodie definitions had the best sensitivity (0.87-0.88 and 95 % confidence intervals (CI) ranging from 0.82-0.93) while PAMI ?#xA0;9 had the best specificity (0.87 with 95 % CI of 0.86-0.88), while its sensitivity was quite low (0.42). In a sample size simulation of a trial aimed at demonstrating a 33 % difference in 30-day mortality between two hypothetical treatments, the number of STEMI patients needed to be screened varied from 4712 for the Brodie definition to 9038 for the PAMI ?#xA0;9 score.
There is a large variability in risk stratification, sensitivity, specificity and predictive values among different scoring systems. These considerations should be taken into account when designing randomised trials.